1. Field of the Invention
The present invention relates to a copper based material of low thermal expansion and high thermal conductivity that is suitable for producing, e.g., a heat sink, in which low thermal expansion coefficient that is comparable to the properties of silicon chips and ceramic boards, and efficient heat releasing property are required. The invention also relates to a method for producing the same.
2. Prior Art
Concerning a material for producing, for instance, a heat sink; a low thermal expansion coefficient and a high heat releasing property are required. As such a material, a copper-molybdenum-based alloy or a copper-tungsten-based alloy is generally used. These materials are employed in order to utilize both the high thermal conductivity of copper and the low thermal expansion coefficient of molybdenum or tungsten. For instance, it is disclosed in Patent Gazette: JPA No. S62-284032 (1987) that a material containing the dispersion of molybdenum phase in copper matrix can be obtained by compacting a mixed powder of copper and molybdenum under pressure and subjecting the obtained green compact to sintering at a temperature to generate the liquid phase of copper. In Patent Gazette: JPA No. S59-21032 (1984), materials containing copper dispersion in molybdenum skeleton or tungsten skeleton are disclosed that is produced by forming the skeletal structure through sintering molybdenum powder or tungsten powder at high temperatures and it is then subjected to copper infiltration.
Related Arts
[Patent Gazette 1] JPA No. S62-284032 (1987) and
[Patent Gazette 2] JPA No. S59-21032 (1984)